Traditional relational database management systems have inherent problems representing clinical and epidemiological data and supporting easy data access by the clinical investigator. Emerging object database technology holds the promise of addressing these problems and providing a data environment for clinical and epidemiological research that is both more flexible and more accessible. The Phase I project will explore this potential y constructing an object- oriented clinical dat a base framework and using it to represent an important existing longitudinal database of menstrual and reproductive history data maintained by the Tremin Trust Research Program on Women's Health. The project is based on collaborations with scientists at th University of Utah and at Children's Hospital in Boston. Phase II will develop and test a full software prototype of an object-oriented clinical data management system, based on the foundations laid in Phase I. The major anticipated technical innovation is the use of object-oriented computer technology to define new data representations that capture the full richness of clinical information and make it more easily accessible to the clinical investigator. The major anticipated health-related contribution is an improved ability to manage, retrieve, analyze, and communicate the content of major clinical and epidemiological data resources. PROPOSED COMMERCIAL APPLICATION: The proposed software addresses significant shortcomings in the management and analysis of clinical and epidemiological study data in academia, government, and industry. The founders of Belmont Research have direct experience in the successful development and marketing of several earlier-generation clinical data management systems.